This invention relates to a backwash adaptor for a swimming pool filter system which enables backwashing of the filter to be carried out without loss of water from the swimming pool itself so that the backwashing is carried out with fresh water from an alternative source.
A swimming pool filter system generally includes a skimmer which allows water to run from the upper surface of the pool into the skimmer body from which it is extracted by an extraction pipe and carried to a filter for filtration of any solid material before returning of the filtered water to the pool. A pump is positioned in the line driving the water from the skimmer body through the filter and back to the pool.
For effective and proper maintenance of the pool water it is necessary to backwash the filter on a regular basis at least several times per week and preferably daily. Backwashing involves the reversal of the direction of flow of the water through the filter so that the trapped solids are carried away from the filter by the reverse flow water and then discarded with the water. For this purpose the filter generally includes a valve arrangement which can be manually operated to reverse the direction of flow so that the water withdrawn from the pool instead of being filtered acts as the backwashing medium. It is of course not possible to return the reverse flow fluid to the pool since this would merely return the extracted solids to the pool. It is therefore necessary to discard the water from the pool either into an area of the yard surrounding the pool or into the sewer system.
The pool water thus extracted and discarded is of course heated and contains significant quantities of chemicals necessary for keeping the pool waterfresh. Very approximately one and a half percent of the pool water is necessary to carry out an effective backwashing and if repeated at the preferred rate, this will discard a significant amount of the pool water. This pool water must of course be replaced, with of course the necessity to reheat the fresh water and to add the necessary further chemicals to the fresh water.